11231320021 has 4 divisors (see below), whose sum is σ = 11232417292. Its totient is φ = 11230222752.

The previous prime is 11231320019. The next prime is 11231320039. The reversal of 11231320021 is 12002313211.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4845552100 + 6385767921 = 69610^2 + 79911^2 .

It is a cyclic number.

It is not a de Polignac number, because 11231320021 - 2¹ = 11231320019 is a prime.

It is a super-2 number, since 2×11231320021² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11231319977 and 11231320004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11231320921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 533136 + ... + 553801.

It is an arithmetic number, because the mean of its divisors is an integer number (2808104323).

Almost surely, 2^11231320021 is an apocalyptic number.

It is an amenable number.

11231320021 is a deficient number, since it is larger than the sum of its proper divisors (1097271).

11231320021 is a wasteful number, since it uses less digits than its factorization.

11231320021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1097270.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 11231320021 its reverse (12002313211), we get a palindrome (23233633232).

The spelling of 11231320021 in words is "eleven billion, two hundred thirty-one million, three hundred twenty thousand, twenty-one".